1. Field of the Invention
The present invention relates to data storage libraries that house a plurality of data storage tape cartridges such as magnetic tape cartridges. Such libraries include drives for reading data from the tape cartridges or writing data onto the tape cartridges and further include a so-called robotic transporter to move the tape cartridges between tape cartridge storage locations and the drive or between storage locations. The present invention generally relates to systems for and methods of improving the efficiency of a data storage library system.
2. Description of Related Art
The speed with which an automated data storage library performs its operations is an extremely important factor in connection with assessing the desirability and the commercial value of a library. With increased speed of library operations, fewer libraries are needed, or fewer library components, such as robots and drives, are needed.
Commands from a host computer to move tape cartridges to perform read/write operations, and the like, are virtually instantaneous, but may be queued or backlogged if the library robot and drives are not capable of implementing the commands as soon as the host computer issues the commands. Thus, the speed with which a robot moves to grasp a tape cartridge from a storage location and transfers the tape cartridge to a drive, the speed with which the drive performs the read/write operations, and the speed with which the robot obtains the tape cartridge from the drive and return the tape cartridge to the storage location, as well as the speed with which a robot transfers a tape cartridge from one storage location to another storage location, are all important factors in the overall speed and efficiency of library operations. Ideally, the library will work with such speed and efficiency that there will never be any queue or backlog of commands from the host computer—an achievement that is very difficult to attain.
It is to innovations in view of this background and with the goal of improving the efficiency of operations of an automated data storage library, that the present invention is directed.